.crumbs {
  margin-top: 1.4rem;
  padding-top: 1.2rem;
  display: flex;
  align-items: center;
  gap: 0.4rem;
  font-size: 0.9rem;
  color: var(--ink-muted);
}

.crumbs a {
  color: var(--ink-muted);
  text-decoration: none;
}

.crumbs a:hover {
  color: var(--accent-dark);
}

.crumbs .sep {
  color: var(--border);
}

.crumbs .cur {
  color: var(--ink);
}

.tag-filter {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
  margin-bottom: 2rem;
}

.tag-filter button {
  border: 1px solid var(--border);
  background: var(--bg-panel);
  color: var(--ink-muted);
  border-radius: var(--r-pill);
  padding: 0.5rem 1.1rem;
  font-size: 0.9rem;
  font-family: var(--font-body);
  cursor: pointer;
  transition: background 0.2s ease, color 0.2s ease, border-color 0.2s ease;
}

.tag-filter button:hover {
  border-color: var(--accent);
  color: var(--ink);
}

.tag-filter button.is-on {
  background: var(--ink);
  color: var(--white);
  border-color: var(--ink);
}

.post-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.6rem;
}

.post-empty {
  color: var(--ink-muted);
  padding: 2rem 0;
}

.post-card {
  display: block;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--r-lg);
  padding: 1.6rem;
  text-decoration: none;
  color: var(--ink);
  box-shadow: var(--shadow-card);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
  min-width: 0;
}

.post-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lift);
}

.post-meta {
  display: flex;
  align-items: center;
  gap: 0.8rem;
  margin-bottom: 0.8rem;
  font-size: 0.82rem;
  color: var(--ink-muted);
}

.post-tag {
  background: var(--accent-soft);
  color: var(--accent-dark);
  border-radius: var(--r-pill);
  padding: 0.2rem 0.7rem;
  font-weight: 600;
}

.post-meta time {
  font-family: var(--font-mono);
}

.post-title {
  font-size: 1.15rem;
  line-height: 1.4;
  margin: 0 0 0.6rem;
  color: var(--ink);
}

.post-sum {
  font-size: 0.92rem;
  line-height: 1.7;
  color: var(--ink-muted);
  margin: 0;
}

.post-preview-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.6rem;
}

/* 文章正文页 Hero */
.post-hero {
  padding: 2.2rem 0 1.4rem;
  border-bottom: 1px solid var(--border);
  margin-bottom: 2rem;
}

.post-hero-meta {
  display: flex;
  align-items: center;
  gap: 0.9rem;
  margin-bottom: 1rem;
  font-size: 0.85rem;
  color: var(--ink-muted);
}

.post-hero-meta time {
  font-family: var(--font-mono);
}

.post-read-time {
  font-family: var(--font-mono);
}

.post-hero h1 {
  font-family: var(--font-display);
  font-size: clamp(1.8rem, 3.6vw, 2.6rem);
  line-height: 1.3;
  color: var(--ink);
  margin: 0 0 0.9rem;
}

.post-hero-lede {
  font-size: 1.05rem;
  color: var(--ink-muted);
  line-height: 1.7;
  max-width: 720px;
}

/* 文末下载引导卡 */
.dl-invite {
  margin-top: 3rem;
  padding: 2.2rem;
  background: var(--bg-panel2);
  border-radius: var(--r-lg);
  color: var(--txt-on-dark);
}

.dl-invite h3 {
  font-family: var(--font-display);
  font-size: 1.4rem;
  margin: 0 0 0.6rem;
  color: var(--white);
}

.dl-invite p {
  color: var(--txt-on-dark-dim);
  margin: 0 0 1.4rem;
  line-height: 1.7;
}

.dl-invite .cta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
}

/* 延伸阅读 */
#related-posts {
  margin-top: 3rem;
}

.related-heading {
  font-family: var(--font-display);
  font-size: 1.3rem;
  color: var(--ink);
  margin: 0 0 1.2rem;
}

.related-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.2rem;
}

.related-card {
  display: block;
  background: var(--bg-panel);
  border: 1px solid var(--border);
  border-radius: var(--r-md);
  padding: 1.2rem;
  text-decoration: none;
  color: var(--ink);
  transition: border-color 0.2s ease, transform 0.2s ease;
  min-width: 0;
}

.related-card:hover {
  border-color: var(--accent);
  transform: translateY(-3px);
}

.related-card .post-meta {
  margin-bottom: 0.5rem;
  font-size: 0.78rem;
}

.related-title {
  font-size: 0.98rem;
  line-height: 1.5;
  color: var(--ink);
  margin: 0;
  display: block;
}

/* 上一篇 / 下一篇 */
#post-nav {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.2rem;
  margin-top: 2rem;
}

.pn-item {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  padding: 1.2rem 1.4rem;
  border: 1px solid var(--border);
  border-radius: var(--r-md);
  text-decoration: none;
  color: var(--ink);
  transition: border-color 0.2s ease;
  min-width: 0;
}

.pn-item:hover {
  border-color: var(--accent);
}

.pn-next {
  text-align: right;
  grid-column: 2;
}

.pn-dir {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--ink-muted);
}

.pn-title {
  font-size: 0.95rem;
  line-height: 1.5;
  color: var(--ink);
}

@media (max-width: 900px) {
  .post-grid,
  .post-preview-grid,
  .related-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 640px) {
  .post-grid,
  .post-preview-grid,
  .related-grid {
    grid-template-columns: 1fr;
  }

  #post-nav {
    grid-template-columns: 1fr;
  }

  .pn-next {
    grid-column: 1;
    text-align: left;
  }
}